Some believe the origin of the term Loop is derived from the cable car, and especially those of two lines that shared a loop, constructed in 1882, bounded by Van Buren, Wabash, Wells, and Lake.[2][3] Other research has concluded that "the Loop" was not used as a proper noun until after the 1895–97 construction of the Union elevated railway loop.[4]

Fort Dearborn was established in 1803, the first American-backed settlement in the area. When Chicago was initially platted in 1830, it included what is now the Loop north of Madison Street and west of State Street. Except for the Fort Dearborn reservation (which wouldn't become part of the city until 1839) and land reclaimed from Lake Michigan, the entirety of what is now the Loop was part of the Town of Chicago when it was initially incorporated in 1833 and the area was bustling by the end of the 1830s.

Passenger lines reached seven Loop-area stations by the 1890s, with transfers from one to the other being a major business for taxi drivers prior to the advent of Amtrak in the 1970s and the majority of trains being concentrated at Chicago Union Station. The construction of a streetcar loop in 1882 and the elevated railway loop in the 1890s gave the area its name and cemented its dominance in the city; by 1948 an estimated one million people came to and went from the Loop each day. Afterwards, suburbanization caused a decrease in the area's importance. Starting in the 1960s, however, the presence of an upscale shopping district caused the area's fortunes to increase.

From the 1890s to the 1940s, local aldermen "Bathhouse John" Coughlin and Michael "Hinky Dink" Kenna led the so-called "Gray Wolves" of Chicago, a notoriously corrupt group of aldermen. They hosted the First Ward Ball in the area at the Chicago Coliseum, an event that brought together various people of ill repute and by the time of its forced closure in 1909 raised over $50,000 a year ($1,000,000 in 2018) for the aldermen. Coughlin served from 1892 until his death in 1938; having served for 46 years, he was the longest-serving alderman in Chicago history until his record was broken in November 2014 by Ed Burke of the 14th ward.[5] He was from the area and owned several bathhouses in it, although in his later years he lived in the nearby Near South Side.[6] Kenna served as alderman from 1897 to 1923, when he stepped down in favor of Coughlin when the number of aldermen per ward decreased from two to one, and again from 1939 to 1943 upon Coughlin's death.

Corruption in the area would continue throughout the 20th century. Subsequent aldermen John D'Arco Sr. and Fred Roti were accused of being fronts for the mob, and the 1st ward was moved in 1992 from the Loop up north to its current position in West Town in an effort to stymie corruption, the Loop itself being dispersed across several wards.

Loop architecture has been dominated by skyscrapers and high-rises since early in its history. Notable buildings include the Home Insurance Building, considered the world's first skyscraper (demolished in 1931); the Chicago Board of Trade Building, a National Historic Landmark; and Willis Tower, the world's tallest building for nearly 25 years. Some of the historic buildings in this district were instrumental in the development of towers. Chicago's street numbering system – dividing addresses into North, South, East, and West quadrants originates in the Loop at the intersection of State Street and Madison Street.

The Chicago River and its accompanying Chicago Riverwalk, which delineates the area, also provides entertainment and recreational opportunities, including the annual dyeing of the river green in honor of St. Patrick's Day. Trips down the Chicago River, including architectural tours, by commercial boat operators are great favorites with both locals and tourists alike.

The Loop is the seat of Chicago's government. It is also the government seat of Cook County and houses an office for the governor of the State of Illinois. The city and county governments are situated in the same century-old building. Across the street, the Richard J. Daley Center accommodates a famous Picasso sculpture and the state law courts. Given its proximity to government offices, the Center's plaza serves as a kind of town square for celebrations, protests and other events.

From the city's incorporation and division into wards in 1837 to 1992, the Loop as currently defined was at least partially contained within the 1st ward.[20] From 1891 to 1992 it was entirely within the 1st ward and was coterminous with it between 1891 and 1901.[21] It was while part of the 1st ward that it was represented by the Gray Wolves. The area has not had a Republican alderman since Francis P. Gleason served alongside Coughlin from 1895 to 1897.[22] (Prior to 1923, each ward elected two aldermen in staggered two-year terms).[22]

In the Illinois Senate most of the community area is in District 3, represented by Democrat Mattie Hunter, while a large part in the east is part of District 13, represented by Democrat Kwame Raoul, and a very small part in the west is part of District 5, represented by Democrat Patricia Van Pelt.[29]

The Chicago River is the south border of the Near North Side (right) and the north border of the Loop; the Loop's Near East Side is to the left in this picture.

According to the 2010 census, 29,283 people live in the neighborhoods in or near the Loop. The median sale price for residential real estate was $710,000 in 2005 according to Forbes.[31] In addition to the government, financial, theatre and shopping districts, there are neighborhoods that are also part of the Loop community area. For much of its history this Section was used for Illinois Central rail yards, including the IC's Great Central Station, with commercial buildings along Michigan Avenue. The New Eastside is a mixed-use district bordered by Michigan Avenue to the west, the Chicago River to the north, Randolph Street to the south, and Lake Shore Drive to the east. It encompasses the entire Illinois Center and Lakeshore East[32] is the latest lead-developer of the 1969 Planned Development #70, as well as separate developments like Aon Center, Prudential Plaza, Park Millennium Condominium Building, Hyatt Regency Chicago, and the Fairmont Hotel. The area has a triple-level street system and is bisected by Columbus Drive. Most of this district has been developed on land that was originally water and once used by the Illinois Central Railroad rail yards. The early buildings in this district such as the Aon Center and One Prudential Plaza used airspace rights in order to build above the railyards. The New Eastside Association of Residents (NEAR) has been the recognized community representative (Illinois non-profit corporation) since 1991 and is a 501(c)(3) IRS tax-exempt organization.

The triple-level street system allows for trucks to mainly travel and make deliveries on the lower levels, keeping traffic to a minimum on the upper levels. Through north–south traffic uses Middle Columbus and the bridge over the Chicago River. East–west through traffic uses either Middle Randolph or Upper and Middle Wacker between Michigan Avenue and Lake Shore Drive.

Printer's Row, also known as Printing House Row, is a neighborhood located in the southern portion of the Loop community area of Chicago. It is centered on Dearborn Street from Ida B. Wells Drive on the north to Polk Street on the south, and includes buildings along Plymouth Court on the east and Federal Street to the west. Most of the buildings in this area were built between 1886 and 1915 for house printing, publishing, and related businesses. Today, the buildings have mainly been converted into residential lofts. Part of Printer's Row is an official landmark district, called the Printing House Row District.[33] The annual Printers Row Lit Fest is held in early June along Dearborn Street.[34]

Dearborn Station at the south end of Printers Row, is the oldest train station still standing in Chicago; it has been converted to retail and office space. Most of the area south of Ida B. Wells Drive between Lake Michigan and the Chicago River, excepting Chinatown, is referred to as the South Loop. Perceptions of the southern boundary of the neighborhood have changed as development spread south, and the name is now used as far south as 26th Street.

The neighborhood includes former railyards that have been redeveloped as new-town-in-town such as Dearborn Park and Central Station. Former warehouses and factory lofts have been converted to residential buildings, while new townhouses and highrises have been developed on vacant or underused land. A major landowner in the South Loop is Columbia College Chicago, a private school that owns 17 buildings.

The South Loop was historically home to vice districts, including the brothels, bars, burlesque theaters, and arcades. Inexpensive residential hotels on Van Buren and State Street made it one of the city's Skid Rows until the 1970s. One of the largest homeless shelters in the city, the Pacific Garden Mission, was located at State and Balbo from 1923 to 2007, when it moved to 1458 S. Canal St.[35]

The Loop Retail Historic District is a shopping district within the Chicago Loop community area in Cook County, Illinois, United States. It is bounded by Lake Street to the north, Ida B. Wells Drive to the south, State Street to the west and Wabash Avenue to the east. The district has the highest density of National Historic Landmark, National Register of Historic Places and Chicago Landmark designated buildings in Chicago. It hosts several historic buildings including former department store flagship locations Marshall Field and Company Building (now Macy's at State Street), and the Sullivan Center (formerly Carson, Pirie, Scott and Company Building).

The Chicago Loop Alliance is located at 27 East Monroe,[45] the Chicagoland Chamber of Commerce is located in an office in the Aon Center, the French-American Chamber of Commerce in Chicago has an office in 35 East Wacker, the Netherlands Chamber of Commerce in the United States is located in an office at 303 East Wacker Drive, and the US Mexico Chamber of Commerce Mid-America Chapter is located in an office in One Prudential Plaza.[46]

Spertus Institute, a center for Jewish learning & culture, is located at 610 S. Michigan Ave. Graduate level courses (Master and Doctorate) are offered in Jewish Studies, Jewish Professional Studies and Non-profit Management. Also housed in the Spertus building is Meadville Lombard Theological School which is affiliated with the Unitarian Universalist Association, a liberal, progressive seminary offering graduate level theological and ministerial training. East-West University is located at 816 S Michigan Ave.